J Biomed Clin Res Volume 7 Number 1, 2014

DOI: 10.1515/jbcr-2015-0117 Review

DOES MEFLOQUINE (LARIAM® ) THERAPY IMPROVE THE PROGNOSIS OF HUMAN JC POLYOMAVIRUS-INDUCED PROGRESSIVE MULTIFOCAL LEUKOENCEPHALOPATHY?

Zlatko N. Kalvatchev, Summary Iliya T. Tsekov Progressive multifocal leukoencephalopathy (PML) is a Laboratory of Molecular Virology caused by with Military Medical Academy Polyomavirus hominis 2, popularly known as JC (JCV). The disease is usually fatal as it develops due to the Sofia, Bulgaria progressive destruction of in multiple brain foci. Several substances that show effect against JCV have been investigated. However, only the antimalarial drug mefloquine has been reported to significantly influence the viral replication both in vitro and following in vivo therapy with good penetration and distribution of the drug at efficacious concentrations into the (CNS). The current material presents some of the available published data, suggesting that the activity of mefloquine against JCV should be considered for treatment of patients with PML. Keywords: progressive multifocal leukoencephalopathy, PML, human polyoma virus JC, JCV, Lariam® , mefloquine

The virus

Human polyomavirus 2 (JCV) is a double-stranded DNA virus (Fig. 1) [1]. According to the presence of viral-specific antibodies it is believed that in 65% to 90% of the human population, asymptomatic with JCV occur [2]. Moreover, 20% to 40% of individuals have been proved to persistently shed the virus with their urine and that viral particles are present in the tubular epithelial cells of the kidneys. Both of these indicate that the infection caused by JCV may be characterised as persistent and chronic in a significant number of the healthy Corresponding Author: human population. Despite the high level of Zlatko N. Kalvachev infection and viral prevalence, a lytic type of JC e-mail: [email protected] replication in the affected oligodendrocytes from the central nervous system (CNS) rarely occurs. Most often, if an underlying severe cellular immune Received: May 15, 2014 deficit is present, this may lead to eventual Revision received: July 24, 2014 destruction of the infected glial cells, followed by Accepted: November 24, 2014 multiple lesions detected by MRI in the white matter

3 © Medical University Pleven J Biomed Clin Res Volume 7 Number 1, 2014

of the brain and progressive demyelination antibodies like the ones applied for management termed progressive multifocal leukoencephalo- of (MS) and Crohn's disease, pathy or PML [2, 3]. led to unexpected side effects and reports for development of, or increased risk for PML [2, 3]. Potent suppression of the cellular immune system seems to be responsible for reactivation of JCV and subsequent development of PML [4]. Moreover, transfer of altered viral to the CNS via infected B-lymphocytes may be facilitated even following transient cellular [5], and neurovirulent JCV strains may progressively affect the oligo- dendrocytes and . The onset of the disease and its severity is determined by the ability of the host to initiate and maintain a robust cellular immune response against replicating JCV [6]. Various T-lymphocytes play an impor- tant part in the host defence mechanisms against like JCV, such as the CD4+ type lymphocytes, which stimulate a cytotoxic immune response, mediated by CD8+ T-cells [7]. Figure 1. Genomic structure of Human Active destruction of glial cells harbouring polyomavirus JC (JCV): JCV has covalently linked replicating viruses involves the effect of circular (5130 base pair in size) with differentiated CD8+ cytotoxic T-lymphocytes bidirectiоnal regulatоry and coding regions. The that are specific for JCV, which in turn contribute regulatory region cоntains the origin of DNA to containing the development of PML [6]. replicatiоn and /enhancer elements. The cоding regions are divided intо an early and late region. The early regiоn encodes regulatory prоteins, small and large T antigen. The late cоding region encodes viral structural prоteins (VP-1, VP-2 and VP-3) and a shоrt regulatory peptide, agnоprotein. Form reference [1].

The disease

Although it is a rare disease, PML is frequently fatal and most often develops in some immunocompromised individuals in the setting of uncontrolled lytic JCV replication in specific brain cells (Fig. 2). PML was reported as a relatively rare condition until the mid-80s of 20th Figure 2. Progressive multifocal century and mainly occurred in patients with leukoencephalopathy (PML): macroscopic view. underlying neoplastic disease as a cause of [Cited 2014 May 08]. Available from impaired immune function or more rarely in http://library.med.utah.edu/WebPath/TUTORIAL/AI DS/AIDS076.html allograft recipients due to the application of immunosuppressive drugs. The onset of the AIDS pandemic marked a significant increase in the incidence of PML. It was documented that approximately 3% to 5% of the individuals living The therapy with HIV developed PML, classifying the disease as an AIDS-defining illness. More recently, the Therapeutic agents that have proven their effect advance in treatment of autoimmune and have officially been registered for inflammatory diseases with monoclonal application with PML patients are not available so far. Antiviral and antineoplastic medications 4 © Medical University Pleven Kalvatchev Z., Tsekov I. Does mefloquine (lariam® ) therapy improve the prognosis...

like cytarabine, cidofovir, and topotecan have been used in a number of preclinical reports and case studies. Although it has been suggested that these medications possess a potential anti-PML effect, larger-scale case-controlled studies failed to determine a marked efficacy from their application [8-10]. Currently, it is assumed that the most effective approach for treatment of PML is reconstitution of the immune system of patients. For example, after the introduction of highly active antiretroviral therapy (HAART) the mortality rate of PML in individuals with HIV/AIDS was significantly reduced from 90% to 50%, which has remained the single most effective action Figure 3. Chemical structure of mefloquine [11]. (CH FNo) A similar approach in patients that have 17 16 6 2 developed PML after application of immuno- suppressive drug regimens involves reduction of blocking the entry of the viral particles into the dosage, which in term may stop or even improve cell. A randomised, rater-blinded clinical trial the clinical symptoms [12]. Nevertheless, an designed to assess the effectiveness of immune reconstitution is not always possible and mefloquine in PML patients is currently under is prone to failure even when possible. Therefore, way. The primary end point for this study is JC therapeutics directly targeting JCV ought to be viral DNA quantitation in the CSF, and the discovered, tested and implemented. secondary end point is neurological status and Mefloquine (Fig. 3) is a compound with anti- brain magnetic resonance imaging. malarial properties and has extensively been used Recent publications have suggested that for prophylaxis and treatment of this disease [13]. mefloquine is effective against JC virus and PML A research carried out by Brickelmaier et al. in progression, respectively [14, 16-18]. 2009 screened several thousand already known Brickelmaier et al., 2009 reported that, in drugs and tested selected ones for activity against vitro, mefloquine could inhibit the viral JCV on an in vitro model of human replication rate and infectivity in cultured human infection. The results showed that mefloquine glial cells and astrocytes at micromolar could inhibit the replication of JCV when applied concentrations. In addition, mefloquine is known in concentrations that had previously been to pass the blood-brain barrier. The results from a documented to accumulate in the CNS of patients second set of experiments by the same group treated with mefloquine for malaria [14]. suggested that mefloquine was effective against Moreover, the inhibitory activity of mefloquine two different JC virus strains in cell culture even was established against JCV strains that were after the onset of infection. Data from additional typically identified to cause PML. Also, an experiments done in vitro showed that animal model to effectively study PML is not mefloquine could supress the development of available [14]. On the other hand, the application infection with three different JCV isolates of mefloquine in humans has a generally (Mad1, Mad4 and M1/SVE) grown in three favourable safety profile as this drug has a long different cell types (transformed human glial and substantial usage history [15]. Thus, it was (SVG-A) cells, primary human foetal glial cells, possible to initiate a trial designed to evaluate the and primary human astrocytes). The use of real- clinical activity of mefloquine in PML patients, time quantitative PCR helped to determine the although animal or further in vitro studies were number of viral copies in the cultured cells and not performed. showed inhibition of JCV DNA replication by Mefloquine is known to accumulate in the mefloquine [14]. CNS at much higher levels than its effective McGuire J., et al., 2011 treated a PML patient concentration. The main mechanism thought to in the setting of HIV infection with mirtazapine be involved in the reported anti-JC viral activity for 5 months and with mefloquine for 3 days at a is inhibition of viral replication rather than daily dose of 250 mg, followed by weekly 5 © Medical University Pleven J Biomed Clin Res Volume 7 Number 1, 2014

administration of 250 mg for 9 months. The mefloquine was then continued with a single dose control MRI after 10 months from the beginning of 250 mg a week. Three months after the of the study did not show any new zones of introduction of treatment, the tests did not detect demyelination, and throughout the affected brain viral DNA in the , plasma, and a decreased enhancement was observed [18]. urine. The patient was found to be with increased Scarce data exist regarding recovery in non- liver enzyme levels (aspartate transaminase and AIDS-associated PML. Cessation of immune alanine transaminase) while on 500 mg suppression or immune reconstitution, similar to mefloquine twice a week. A reduction in the dose the start of HAART in AIDS patients, may to 250 mg once a week resulted in recovery of the improve the survival chances of patients already liver enzyme levels, and disease stabilisation manifesting symptoms of PML. Patients with continued. No other side effects were noted PML as an AIDS-defining illness were during the mefloquine intake. Twenty months documented with a mean survival time after after the onset of symptoms, the patient remained diagnosis of 7.5 months [19]. In patients with a clinically stable without further neurological known diagnosis of AIDS, the mean survival time decline. Improvement was seen in voice was only 3.2 months. Longer survival time was projection, nausea and vomiting. No JC viral associated with increased CD4+ cell counts. DNA was detectable in the CSF, and the Whether there is a spontaneous recovery of mefloquine therapy was discontinued. Although biopsy-proven PML within the non-AIDS the clinical improvement of that patient clearly population has not been well reported in followed the initiation of mefloquine, the literature. efficacy and safety of the drug for treatment of In non-AIDS patients, PML is seen in the PML can only be determined by additional context of systemic sarcoidosis treated with studies, preferably randomised and controlled steroids. More rarely, sarcoidosis has been trials. Moreoever, the dosing of mefloquine in the associated with PML before the onset of steroid setting of PML remains to be determined. therapy. A recent presentation of a case report and This controversy is even greater as review of the literature states that only three cases mefloquine therapy has been described to be of PML developed in patients with symptoms of ineffective in several case reports [21]. Recently, sarcoidosis in the absence of immune modulation not one proof-of-concept study succeeded to with steroids or other agents [20]. It is likely that establish sufficient evidence for an anti-JCV the characteristics of the sarcoid disease itself activity of mefloquine [22]. Further predispose patients with systemic sarcoidosis to investigations are needed to in order to prove reactivation of JCV and development of PML. In whether mefloquine therapy improves the this case, the short course of steroids is unlikely to prognosis of human JC polyomavirus-induced have triggered the onset of infection by JCV, progressive multifocal leukoencephalopathy. especially since disease progression has continued long after the discontinuation of Conclusion prednisone. The ongoing neurological deterioration until the introduction of mefloquine The antimalarial drug mefloquine is shown to could suggest either coincidental recovery or a inhibit the replication of different JCV isolates role for mefloquine in the recovery. and to successfully accumulate in the tissues of Schroder A, et al., 2010 [16] described a case the CNS. Thus, this drug has a potential to be of PML associated with treatment effectively applied as part of the complex and its successful management with a therapy therapeutic regimen for management of PML. that was well tolerated and included mefloquine Controlled randomized clinical trials with PML at dosage used for prophylaxis of malaria patients are currently under way, aiming to combined with mirtazapine. Following the determine the clinical efficacy of mefloquine in diagnosis of PML, 5 courses of plasma exchange terms of viral inhibition, protection of the CNS were applied to the patient in order to improve the from the damage and improvement of the related clearance of natalizumab from the blood symptoms. Furthermore, it is highly warranted, circulation. The treatment also included that systematic studies are carried out to mirtazapine at a daily dose of 60 mg, and determine the optimal dosage and underlying mefloquine was administered orally at a loading acting mechanisms of this compound when used dose of 250 mg for 3 days. The therapy with for treatment of PML. 6 © Medical University Pleven Kalvatchev Z., Tsekov I. Does mefloquine (lariam® ) therapy improve the prognosis...

References renal transplant patient. Am J Transplant. 2005;5(5):1151-8. Epub 2005/04/09. doi: 1. Sariyer IK, Akan I, Del Valle L, Kamel Khalili K, 10.1111/j.1600-6143.2005.00800.x. Safak M. Tumor induction by simian and human 13. Roche Laboratories I. Lariam (mefloquine): polyomaviruses. Cancer Ther. 2004;2:85-98. prescribing information. USA: Roche Laboratories; 2. Imperiale MJ, Major EO. Polyomaviruses. In: Fields 2003. BN, Knipe DM, Howley PM, editors. Fields virology. 14. Brickelmaier M, Lugovskoy A, Kartikeyan R, 2. 5th ed. Philadelphia: Wolters Kluwer Health/ Reviriego-Mendoza MM, Allaire N, Simon K, et al. Lippincott Williams & Wilkins; 2007. p. 2264-99. Identification and characterization of mefloquine 3. Tsekov I, Kalvatchev Z, Kulev O, Elenkov I, efficacy against JC virus in vitro. Antimicrob Agents Ferdinandov D. Identification of polyomavirus JC Chemother. 2009;53(5):1840-9. doi: 10.1128/ genome sequences in two HIV-associated PML cases AAC.01614-08. in Bulgaria. Biotechnology & Biotechnological 15. Schlagenhauf P, Adamcova M, Regep L, Schaerer Equipment. 2008;22(3):867-8. MT, Rhein HG. The position of mefloquine as a 21st 4. Tan CS, Koralnik IJ. Progressive multifocal century malaria chemoprophylaxis. Malar J. leukoencephalopathy and other disorders caused by 2010;9:357. doi: 10.1186/1475-2875-9-357. JC virus: clinical features and pathogenesis. Lancet 16. Schroder A, Lee DH, Hellwig K, Lukas C, Linker neurology. 2010;9(4):425-37. doi: 10.1016/S1474- RA, Gold R. Successful management of 4422(10)70040-5. natalizumab-associated progressive multifocal 5. Boothpur R, Brennan DC. Human polyoma viruses leukoencephalopathy and immune reconstitution and disease with emphasis on clinical BK and JC. J syndrome in a patient with multiple sclerosis. Arch Clin Virol. 2010;47(4):306-12. doi: 10.1016/ Neurol. 2010;67(11):1391-4. doi: 10.1001/ j.jcv.2009.12.006. archneurol.2010.157. 6. Du Pasquier RA, Autissier P, Zheng Y, Jean-Jacques 17. Gofton TE, Al-Khotani A, O’Farrell B, Ang LC, J, Koralnik IJ. Presence of JC virus-specific CTL in McLachlan RS. Mefloquine in the treatment of the cerebrospinal fluid of PML patients: rationale for progressive multifocal leukoencephalopathy. J immune-based therapeutic strategies. Aids. Neurol Neurosurg Psychiatry. 2011;82(4):452-5. 2005;19(18):2069-76. doi: 10.1136/jnnp.2009.190652. 7. Koralnik IJ. New insights into progressive multifocal 18. McGuire JL, Fridman V, Wuthrich C, Koralnik IJ, leukoencephalopathy. Curr Opin Neurol. Jacobs D. Progressive multifocal 2004;17(3):365-70. leukoencephalopathy associated with isolated CD8+ 8. Aksamit AJ. Treatment of non-AIDS progressive T-lymphocyte deficiency mimicking tumefactive multifocal leukoencephalopathy with cytosine MS. J Neurovirol. 2011;17(5):500-3. doi: 10.1007/ arabinoside. J Neurovirol. 2001;7(4):386-90. doi: s13365-011-0045-2. 10.1080/ 13550280152537292 19. Fong IW, Toma E. The natural history of progressive 9. De Luca A, Ammassari A, Pezzotti P, Cinque P, multifocal leukoencephalopathy in patients with Gasnault J, Berenguer J, et al. Cidofovir in addition to AIDS. Canadian PML Study Group. Clin Infect Dis. antiretroviral treatment is not effective for AIDS- 1995;20(5):1305-10. associated progressive multifocal 20. De Raedt S, Lacor P, Michotte A, Flamez A, Ebinger leukoencephalopathy: a multicohort analysis. Aids. G. Progressive multifocal leukoencephalopathy as 2008;22(14):1759-67. doi: first manifestation of sarcoidosis. Clin Neurol 10.1097/QAD.0b013e32830a5043. Neurosurg. 2008;110(2):186-9. doi: 10.1016/ 10. Hall CD, Dafni U, Simpson D, Clifford D, Wetherill j.clineuro.2007.09.012. PE, Cohen B, et al. Failure of cytarabine in 21. Kobayashi Z, Akaza M, Numasawa Y, Ishihara S, progressive multifocal leukoencephalopathy Tomimitsu H, Nakamichi K, et al. Failure of associated with human virus mefloquine therapy in progressive multifocal infection. AIDS Clinical Trials Group 243 Team. The leukoencephalopathy: report of two Japanese N Engl J Med. 1998;338(19):1345-51. doi: 10.1056/ patients without human immunodeficiency virus NEJM199805073381903. infection. Journal of the neurological sciences. 11. Bossolasco S, Calori G, Moretti F, Boschini A, 2013;324(1-2):190-4. doi: 10.1016/ Bertelli D, Mena M, et al. Prognostic significance of j.jns.2012.11.004. JC virus DNA levels in cerebrospinal fluid of patients 22. Clifford DB, Nath A, Cinque P, Brew BJ, Zivadinov with HIV-associated progressive multifocal R, Gorelik L, et al. A study of mefloquine treatment leukoencephalopathy. Clin Infect Dis. for progressive multifocal leukoencephalopathy: 2005;40(5):738-44. doi: 10.1086/427698. results and exploration of predictors of PML 12. Crowder CD, Gyure KA, Drachenberg CB, Werner J, outcomes. J Neurovirol. 2013;19(4):351-8. doi: Morales RE, Hirsch HH, et al. Successful outcome of 10.1007/s13365-013-0173-y. progressive multifocal leukoencephalopathy in a

7 © Medical University Pleven